The leaking of toxic water from the stricken Fukushima nuclear plant will not affect Tokyo, according to the head of the city's 2020 Olympic bid Tsunekazu Takeda.

The plant was badly damaged two years ago by the massive earthquake under the ocean and a tsunami.

Last week Tokyo Electric Power Co (Tepco), the plant operator, admitted 300 tonnes of toxic water had leaked from one of the about 1,000 storage tanks on the site before anyone had noticed what was happening.

The spill sparked fears the toxic water may have seeped into the ocean. It was categorised as a Level 3 event, the most serious category since the meltdown itself.

However, Takeda insisted despite the worrying news the leak would not affect either the bid.

Tokyo will learn on Saturday in Buenos Aires whether it, Madrid or Istanbul will host the 2020 Games when the International Olympic Committee (IOC) members vote,

Takeda was speaking before news emerged of new radiation hotspots at four sites around Fukushima's coolant tanks, with one reading showing a dose that would kill a human left exposed to it in four hours.

"There is no risk from Fukushima," Takeda said. "Day-to-day life in Tokyo carries on as normal for its 35 million people.

"The air and water quality is safe. Also the data shows that the radiation level is the same as most cities, like Paris, London and New York. Our main focus is to deliver a great and safe Games"

Takeda, a showjumping rider who competed in the 1972 and 1976 Olympics emulating his father Prince Tsuneyoshi Takeda who rode at the 1936 Games, said by contrast winning the right to host the Games would give the country a huge morale boost after a long period of bad news.

"The tsunami happened hundreds of miles from Tokyo but the consequences were felt by people throughout the country," said Takeda, who is bidding to bring Tokyo its second Olympics having hosted them in 1964.

"The sports community has been at the heart of activity there since. It has shown how important the role athletes can play in society.

"It would be a huge morale boost to the whole country were we to win the right to host the Olympics."